Revert "Reference platform.h by ../src/platform.h - AIX is ignoring -I flags"

This reverts commit 1e8e4d79c885b27831e2196d94987cc2817e0f04.
Merge pull request #3 from vortechs2000/fix_aix

Revert "Reference platform.h by ../src/platform.h - AIX is ignoring -I flags"